1. Field of Invention
The present invention relates to an arrangement (including both method and apparatus) for quantifying sulfur. The arrangement is capable of sensitive detection and quantitative determination of sulfur on site.
The apparatus of the present invention is useful as a high-sensitivity monitor for detection and quantitative determination of the sulfur that is present in semiconductor devices or which has resulted from their fabrication or waste disposal equipment, such as epitaxial growth apparatus (e.g. CVD and LPE furnaces) for compound semiconductors like ZnS, CdS and ZnS.sub.x Se.sub.1-x, high-pressure HB (horizontal Bridgman) furnace, annealing furnace, sulfur pressure annealing furnace, MBE apparatus and organometallic vapor phase epitaxy growth apparatus. The present invention is also suitable for use with melting furnaces for sulfur-containing alloys, ceramics and glass.
2. Prior Art
Few methods are known that are non-destructive, inert to the system and which are capable of on-the-spot detection and quantitative determination of gaseous sulfur. Most of the methods known today for sulfur detection are destructive. Gas chromatography is one of the non-destructive methods for detection and quantitative determination of gaseous substances. However, it is not suitable for sulfur detection because of the following inherent disadvantages: (1) part of the sample in solution being introduced into the measuring system will stick to the inside surface of an injection port, thereby rendering accurate determination of the sample impossible, and (2) the sampling which is indispensable to gas chromatography will disturb the system.
Atomic absorption spectroscopy allows for precise determination of an atomic sample vapor but is theoretically impossible unless the sample is heated to the temperature of atomization (2,000.degree. C.) or above. In addition, no hollow cathode lamp exists that is suitable for use as a source of radiation in atomic absorption spectroscopic analysis of sulfur.